Successful flyback/xformer driver above 3kw

[oneKone]

Just thought I'd put this out there;

How many members here have built a successful flyback/xformer driver that can operate above 3kw (let's say 3-6kw range) without failures. Judging from what I've seen there's not many out there due to the common igbt brick failure (myself is included in this failure scenario)

[Mads Barnkob]

I have only pushed up around 1 kW and burned everything

[davekni]

Does the transformer output need to be high voltage and subject to arc loading to count?

I've build an isolated "PFC" that inputs single-phase 240VAC (or three-phase 208) and outputs isolated adjustable 350-450Vdc.  That feeds my DRSSTC and other projects.  Runs 8-10kW, reliably so far   Uses a TO247 IGBT H-bridge to feed a gapped transformer through series resonant MMC.  Transformer secondary is rectified with SiC diode array to bulk caps at 350-450Vdc.

It can handle shorted load, at least for the duration it takes to charge 44000uF of bulk capacitance.  (Charged 200000uF a few times for my low-frequency QCW experiment.)  The H-bridge runs at the higher resonant frequency of transformer's leakage inductance when output voltage is low, and at the transformer's parallel inductance frequency at normal output voltages.  Current waveforms get a bit more unpredictable at intermediate output voltages.  The H-bridge always switches close to zero current.  However, at intermediate output voltages, switching is sometimes after zero-crossing, causing some hard-switching.

Of course, this is nothing compared to Phoenix' 35kW transformer and resulting arcs:
https://highvoltageforum.net/index.php?topic=1976.msg14755#msg14755